U.S. Pat. No. 7,637,722 which issued to Koepsel, et. al. on Dec. 29, 2009, describes a marine propeller configured to improve maximum velocity, acceleration, and cruise speed characteristics of a marine vessel.
U.S. Patent No. 2007/0065282 which issued to Patterson on Mar. 22, 2007, describes a propeller and apparatus wherein the propeller includes two blade sets of distinctly different geometries, and a propeller hub ring extender.
The patents described above are hereby incorporated by reference in the description of the several implementations set forth below.